Facile fabrication of polyacrylate-siloxane antifouling coatings with self-generated biomimetic surface

Antifouling coatings with biomimetic micro-nano structure have been widely explored for the replacement of traditional self-polishing coatings that relied on high content of biocides. However, their application is limited by the complicated preparation process as well as the lack of antibacterial effect and durability of micro-nano structure. Herein, a bactericide-free antifouling coating with capability to self-generate biomimetic surface was prepared using trimethoxysilyl/triisopropylsilyl ester-bearing polyacrylate and amino-silane coupling agent. Owing to the spontaneous phase separation of amino-silane, a micro-nano textured surface with both underwater superoleophobicity and alkaline hydration layer was generated under seawater immersion, mimicking the anti-adhering and bactericidal functions of the skins of pilot whales and dolphins. Interestingly, identical self-polishing rate and stable biomimetic surface were exhibited both in static and dynamic immersion tests, resulting from the combined action of the micro-nano structure and the alkaline hydration layer. Although no bactericide was contained, the coating based on [3-(2-aminoethyl)aminopropyl]trimethoxysilane possessed sterilization rate of 97.3 % ( E. coli ) and anti-algae rate of 85.1 % ( Chlorella sp.), and could maintain its sterilization rate at 93.1 % and 94.2 % even after 15 days of static or dynamic immersion, respectively. Meanwhile, the coating possessed superior antifouling performance and durability over conventional biomimetic surfaces in the actual marine environment, which came from the combination of micro-nano structure with intrinsic alkalinity and self-regeneration ability. Overall, our work would provide a new and practical strategy for the development of biomimetic antifouling coatings.